From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id B7C8E7F37 for ; Mon, 26 Oct 2015 15:54:12 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay3.corp.sgi.com (Postfix) with ESMTP id 3D76AAC001 for ; Mon, 26 Oct 2015 13:54:09 -0700 (PDT) Received: from ipmail04.adl6.internode.on.net (ipmail04.adl6.internode.on.net [150.101.137.141]) by cuda.sgi.com with ESMTP id sDCl0DD2RuCRzuFs for ; Mon, 26 Oct 2015 13:54:06 -0700 (PDT) Date: Tue, 27 Oct 2015 07:54:04 +1100 From: Dave Chinner Subject: Re: [PATCH] xfs: optimise away log forces on timestamp updates for fdatasync Message-ID: <20151026205404.GH8773@dastard> References: <1445396343-4361-1-git-send-email-david@fromorbit.com> <20151022173618.GC13661@bfoster.bfoster> <20151026050720.GG8773@dastard> <20151026114929.GA59738@bfoster.bfoster> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20151026114929.GA59738@bfoster.bfoster> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Brian Foster Cc: sage@redhat.com, xfs@oss.sgi.com On Mon, Oct 26, 2015 at 07:49:29AM -0400, Brian Foster wrote: > On Mon, Oct 26, 2015 at 04:07:20PM +1100, Dave Chinner wrote: > > > Also, is it me or are we sending an unconditional flush in the hunk > > > following the log force call in xfs_file_fsync() (even if we've skipped > > > the log force)? > > > > The flush is needed - fdatasync needs to guarantee the data is > > on stable storage even if no metadata needs to be written to the > > journal. > > > > Ok. Well it's too bad we don't get any feedback about what was written > from the filemap_write_and_wait_range() call. As it is, we send a flush > even if there's nothing to write back. Direct IO still needs cache flushes. Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs